We have developed an automated analysis scheme for meteor head echoobservations by the 46.5 MHz Middle and Upper atmosphere (MU) radar nearShigaraki, Japan (34.85° N, 136.10° E). The analysisprocedure computes meteoroid range, velocity and deceleration as functions oftime with unprecedented accuracy and precision. This is crucial forestimations of meteoroid mass and orbital parameters as well asinvestigations of the meteoroid-atmosphere interaction processes. In thispaper we present this analysis procedure in detail. The algorithms use acombination of single-pulse-Doppler, time-of-flight and pulse-to-pulse phasecorrelation measurements to determine the radial velocity to within a fewtens of metres per second with 3.12 ms time resolution. Equivalently, theprecision improvement is at least a factor of 20 compared to previoussingle-pulse measurements. Such a precision reveals that the decelerationincreases significantly during the intense part of a meteoroid's ablationprocess in the atmosphere. From each received pulse, the target range isdetermined to within a few tens of meters, or the order of a few hundredthsof the 900 m long range gates. This is achieved by transmitting a 13-bitBarker code oversampled by a factor of two at reception and using a novelrange interpolation technique. The meteoroid velocity vector is determinedfrom the estimated radial velocity by carefully taking the location of themeteor target and the angle from its trajectory to the radar beam intoaccount. The latter is determined from target range and bore axis offset. Wehave identified and solved the signal processing issue giving rise to thepeculiar signature in signal to noise ratio plots reported byGalindo et al. (2011), and show howto use the range interpolation technique to differentiate the effect ofsignal processing from physical processes.
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